### Number of 1 Bits LeetCode Solution - The Coding Shala

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In this post, we will learn how to find the Number of 1 Bits in a given integer and will implement its solution in Java.

## Number of 1 Bits Problem

Write a function that takes an unsigned integer and returns the number of '1' bits it has (also known as the Hamming weight).

Example 1:
Input: n = 00000000000000000000000000001011
Output: 3
Explanation: The input binary string 00000000000000000000000000001011 has a total of three '1' bits.

Example 2:
Input: n = 00000000000000000000000010000000
Output: 1
Explanation: The input binary string 00000000000000000000000010000000 has a total of one '1' bit.

Example 3:
Input: n = 11111111111111111111111111111101
Output: 31
Explanation: The input binary string 11111111111111111111111111111101 has a total of thirty-one '1' bits.

## Number of 1 Bits Java Solution

Approach 1

We can use Java's bitCount() method to get the number of 1 bits.

Java Program:

```public class Solution {
// you need to treat n as an unsigned value
public int hammingWeight(int n) {
return Integer.bitCount(n);
}
}
```

Approach 2

By using bit shifting unsigned operation (>>>).

Java Program:

```public class Solution {
// you need to treat n as an unsigned value
public int hammingWeight(int n) {
int ans = 0;
while(n !=0) {
if((n & 1) == 1) ans++;
n = n >>> 1;
}
return ans;
}
}
```

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